Empiricism begins with the hypothesis that there is an objective reality independent of humanity and we may use inductive logic to learn about this reality through our senses. We can experiment and test the validity of our ideas. The scientific method is a method of empirical testing to prevent common fallacies and errors. Empiricism does not assume a priori knowledge. This is also called Philosophical Realism or materialism.
To recap some basic concepts, rationalists believe knowledge is acquired independently of sensory experience. Empiricists argue that knowledge is based on sensory perception. Rationalism involves ‘pure reason’ (priori knowledge); empiricism involves evidence (posteriori knowledge). Rationalism is top-down (deductive); empiricism is bottom-up (inductive).
Consider a stick in a glass of water. To the empiricist, the stick is broken because it visually appears so. However, when the empiricist dips his hand into the water, the stick is obviously not broken. To the rationalist, it’s not broken, but rather the water makes it seem so due to refraction. The rationalist defers to theory (refraction) to justify the stick not being broken, without having to dip his hand to see for himself.
But there are seldom ‘pure empiricists’ or ‘pure rationalists’–it’s usually a hybrid, in which Kant cleverly devised a philosophical device called the ‘synthetic a priori’ to reconcile this. Many empiricists don’t reject all theories of physics (such as Newton’s law of gravitation), if there is abundant experimental evidence to support them. Empiricism leads to theory, the latter which can be defined as an ‘object’ (which Kant called a noumenon), that exists outside of sense or perception. From The theory of phenomena and noumena:
For example, to explain why the wires in an electric toaster are hot, we invoke the underlying cause of an electric current in the wires; the toaster and its wires, and the heat, are phenomenal, and the electricity is noumenal. Or, in modern language, the toaster and the hot wires are empirical and the electricity is theoretical. As David Hume pointed out, there are no empirical causes, only correlations; all causes are underlying — noumenal — or theoretical. Theoretical science tries to describe the noumenal world, and thereby explain the findings of empirical science. Everything you read about molecules, atoms, electrons, quarks, the curvature of space-time, black holes, the Big Bang, etc. is about noumena.
This is related to Platonic idealism, which is different than Idealism as presented by philosophers such as George Berkeley. Platonic abstractions are not spatial, temporal, or mental; hence, they are not compatible with the latter idealism’s emphasis on mental existence. Plato’s Forms include numbers and geometrical figures, making them a theory of mathematical realism. This makes it a form of materialism, and is related to philosophical realism–the belief that the existence of reality is independent of our conceptual schemes, perceptions, linguistic practices, beliefs, etc.
Although realism and materialism are often used interchangeably, realism involves mathematics and Plato’s forms, which are things that are ‘real’ even though they are not physically so. A rationalist is a realist, because rationalists make use of abstractions (like math). The empiricist tends to reject these abstractions, and may gravitate towards materialist interpretations as being the basis of reality (such as dunking his or her hand in the water to verify that the stick isn’t broken, instead of deferring to refraction theory). But realism is like materialism, as the stick being intact is a property that exists outside of the mind, but realism is an abstract approach (use of theory) determine this knowledge (epistemology) and empiricism is sensory (literally, a hands-on approach). Hierarchically, realism is a subset of materialism. So while realism is materialistic, not all materialism is realism (empiricism and materialism, for example, being linked but the former distinct from realism).
Science involves ‘objects’ such as theories that exist independent of perception and mind. Religion is often associated with idealism in that, epistemologically, it requires faith–by ‘pure reason’ alone, establishing a ink between idealism and rationalism. Rationalism can be applied both in a religious context but also a scientific one.
Empiricism and realism are ‘easy’ because the former lends itself to ‘binary thinking’, specifically, verificationism (the doctrine that a proposition is only cognitively meaningful if it can be definitively and conclusively determined to be either true or false). Empiricism, unlike rationalism, takes the easy way out by never having to commit to a theory. If the empiricist can’t observe it through sense, he can simply reject it. But realism is also ‘easy’, in the synthetic sense, by reducing abstractions to objects that we take for grated as ‘true’. It’s easier to just accept that 1+1=2 than try to go further to understand why it’s so. For example, the statement, ‘rising life expectancy is good’. ‘Good’ is abstract and hard to define, besides it being implied (or objectified) that ‘good’ is contrasted from what is ‘bad’. ‘Life expectancy’ is also an object, as it is something that is measured scientifically and exists outside of sensory perception. Most of the media and pundits, whether it’s Bloomberg, Wall St. Journal, or The Economists, deal with things that can be categorized either ‘true’ or ‘false’ (such as ‘the economy is weak’ or ‘the economy is strong’), with evidence brought forth either opposing or supporting the initial premise. Or objects-as-issues (such as wealth inequality, economic growth), that are often reduced to a binary state of being either ‘good’ or ‘bad’.
Idealism tends to reject object-based reasoning. Although idealism may have a grand theory, vision, or narrative (such as eschatology), it doesn’t rely on empirical, sensory, or object-based means of supporting it. [Materialist philosophy also has 'grand narratives', an example being Marxism, which is based on economic theory (an object), not theology.] It avoids reductionism (in terms of rejecting scientific-reduction in the forms scientism, cognitivism, positivism; but it also rejects verificationism (which is a form of reductionism. Idealists aren’t too fond of empiricism, because it tends to be binary and reductive.)–but also idealism rejects low-information discourse, which is related to binary thinking) preferring complicated, nuanced, and circuitous forms of discourse and invoking teleology. For example, for idealist, civil dissenters fit within a ‘grand theory’ of societal collapse. But aren’t dissenters empirical evidence that agrees with ‘grand theory’? Yes, but it doesn’t matter, because to the idealists the reality has already been constructed in his mind. To be fair, this is similar to how physicists rationalize string theory, because the theory can always be modified to account for any evidence that could disprove it. Or in another way, for an idealist, everything is subsumed by the theory. Teleology is a reason or explanation for something in function of its end, purpose or goal. For example, a teleological explanation of why forks have prongs is that this design helps humans eat certain foods; stabbing food to help humans eat is what forks are for. Likewise, a teleological explanation for dissenters is not that they are having a bad day, but rather because they are actors of a grand eschatological narrative. For a materialist, rather then evidence being subsumed by theory, the theory keeps being modified or is so broad as to encompass everything (which is a criticism of string theory).
As an example of ‘easiness’, an empiricist, if asked to predict something, may predict the sun will rise and fall. This is virtually certain to be a correct prediction, based on his empirical observations of the sun rising and setting. A realist would arrive at the same conclusion based on his knowledge about geophysics and astronomy, but to the idealist he too is missing the point of the question, because predictions are not supposed to be ‘obvious’ and the realist is caving into reductionism, just as the empiricist also engages in reductionism. An idealist, counter to what the objectively-determined odds say, in his mind, chooses odds are different.
Predicting economic stability is likely a correct prediction (based on empirical evidence, specifically, economic data and historical data; and ‘microeconomic foundations’–an attempt to apply the principles of science and physics to economics, to make the latter more rigorous) but conflict with an idealist whose ‘grand vision’ is of instability or eschatology. But ‘reality’ and ‘truth’ regarding the social sciences can be hard to define. Two people can bring forth evidence to arrive at opposite conclusions regarding the same issue. It depends how such evidence is interpreted and it’s context. For example, nominally, the national debt is high, but interest payments are low relative to GDP. By avoiding objects and binaries (verificatonism), the idealist may avoid having his beliefs being falsified.
Idealism is a search for Absolute Truth. It assumes there is a design and purpose to the universe and the human mind, and by discovering this purpose they can understand everything.
Idealism creates teleology. Everything has a function and purpose, and therefore everything has a final cause. This world is highly deterministic. Idealists rely almost purely on deductive logic. They create an artificial set of governing axioms. They can then use deductive logic to answer any problem within their Idealist world.
The idealist, in his mind, knows what is true and is not searching for it. Truth (ontology) for the idealist exists in the mind; for the materialist, it’s in objects. Both sides can either bring forth axioms (rationalism) or empirical evidence (empiricism), both of which are under the category of epistemology.
I also disagree here:
Empiricism takes considerably more effort to understand reality, but the ideas it produces are more consistent even if knowledge remains incomplete. Empirical reality may seem dangerous, as it disproves some moral preconceptions in religions and ideologies. Is it not better to accept reality whether it is pleasing or not?…
A real theory can be practiced in reality. Electrical theory: light bulb. Evolution: Genetic Engineering. Creationism: Nothing. Marxism: 100 million dead, but otherwise nothing.
Although empiricism has pretense of knowledge (because of spokespeople like Dennett, Dawkins, Harris and Nye, who use the ‘scientific method’ as a very convenient crutch), idealism is harder because it doesn’t involve ‘shortcuts’ (such as mathematics, sensory perception , scientific method) that materialism and empiricism employ. For a scientist, a sufficiently low ‘p-value’ can be sufficient, but the idealist isn’t placated as easily, asking, ‘but what if…’ or questioning the validity of the data itself. Idealism involves more mental gymnastics (or teleology) to make empirical reality and theory agree (such as reconciling theology with evolution, or sporadic incidents of ‘civil unrest’ as being a harbinger of impending economic and social collapse, not merely some people having a bad day).
Also, the author seems to be stumbling into the oh so tempting trap of scientific absolutism, overplaying his hand. Marxism is actually a materialistic philosophy (because economic theory is at the core of human behavior and reality, not metaphysics), not an idealistic one.
A mistake made by naivete atheists who think they are being clever is assuming that there is dichotomy where Christianity must oppose science, when such a dichotomy doesn’t necessarily exist. Many Christians understand and accept physics and evolution, and it’s possible to be both a Christian and an engineer or a biologist. Religious philosopher David Ray Griffin discusses this in his book God Exists But Gawd Does Not:
David Ray Griffin argues that progress on this issue will be impossible unless we distinguish between two radically different ideas of a divine creator, which he calls “Gawd” and “God.” Whereas there is overwhelming evidence against the existence of Gawd, there is also overwhelming evidence for the reality of God.
Atheists commonly default to this construct or strawman version of god, which the author calls ‘gawd’. An idealist may be well-versed in theory (such as evolution, quantum mechanics, and relativity) but understand that those things are merely approximations of reality, and that there will always be phenomena that cannot be explained by theory. For example, why don’t galaxies spill apart, because they are held together by ‘dark matter’, but the problem is physicists have no idea what dark matter is even though it’s thought to make up five sixths of the universe’s mass. A materialist may argue that there are no phenomena that can’t be explained by theory.
Related, Sean Carroll, in an excellent post Physicists Should Stop Saying Silly Things about Philosophy, opposes attempts to reduce philosophy to competition against science, or that how philosophy must oppose science, arguing that they can complement each other (a philosophical question being answered using physics), a view echoed by American philosopher of science Tim Maudlin, whose work on physics also incorporates philosophical elements.
Philosophy is useful for organizing ideas, beliefs, and concepts about the non-tangible, non-sensory world–things such as politics, epistemology, religion, morality, ethics, perception, consciousness, etc.–into some form of hierarchy or framework, analogous to the concept of categories in math.
Although reductionism is often frowned upon by idealists, it’s hard to avoid objects and binary thinking when trying to be persuasive. In trying to convey an opinion/perspective/declaration about something, that likely implies one opposes its opposite. There was a recent debate on Scott Aaronson’s blog, spawning significant related discussion elsewhere, but also a lot of internecine disagreement. Just saying ‘immigration is bad’ is too simple (object-based reasoning). The appeal of mathematics is once something is proven (either true or false), further discussion is no longer necessary (for that specific math concept, at least), whereas debates in the social sciences an liberal arts can be unending, as they don’t as easily yield to binary outcomes.