Why do we conflate philosophy with psychology?

I’ve been looking at some stuff on the history of philosophy, and happened to chance upon a video by Pewdiepie, a popular general-topic youtube channel, on stoicism.

My view on “stoicism” is fundamentally quite similar to my view on Ayn Rand’s objectivism – it is based on a sound philosophical claim (in the case of stoicism, the only ethical questions are ones about what you can control; in the case of objectivism, people are motivated by values), but the deductions they make from these premises simply do not follow logically.

For example, the stoics deduce from their principle that people should not care about things that they cannot control, or that they should “make peace” with things how they are. But this is no longer a philosophical claim – it is an ethical claim. And your ethics needs axioms, it doesn’t simply follow objectively from self-evident philosophy. Within my ethical system, I can think of several ways to rebut the ethical claims made by the stoics:

• People are poor judges of what they can control.
• Although ethics is about how you should act/what choices you should make, just thinking about some issue may help you come up with “solutions” to it, i.e. figure out what choices are actually available to you.
• Your natural anger/emotions may very well help motivate your actions.
• You may find thinking about something to be a useful intellectual exercise, even if you do not have the power to control it.
• Your job or source of income may require you to adopt a less stoic “personality”.

To be clear, I’m not saying any of the above arguments are actually valid, and their details are not important to me: I’m saying that they could be valid, in the sense that “how should you react to how things are?” is a question that should be analysed as an ethical question, within your ethical premises, by looking at the consequences of your possible reactions.

Pewdiepie then goes on to claim that a number of psychological ideas derive intellectually from stoicism. 

Again – psychological questions cannot simply be answered by philosophy. Philosophy is something that is self-evident, which you understand purely from introspection without the need for any science or observation. Psychology is, at least in principle, a science. It needs reasoning and experimentation, and cannot be derived from philosophy in this sense.

Yet it seems rather widespread to conflate philosophy with psychology – you hear the colloquial use of phrases like “philosophy on life” to refer to facebook-level pop-psychology mumbo-jumbo, etc. And it isn’t just laypeople either: philosophers do it all the time, e.g. “relativists” claiming that their philosophical viewpoint is somehow related to relativity (relatable, isn’t it?), or the Objectivists denying quantum mechanics. 

The reason for this ambiguity, I guess, is historical. The term philosophy in Greece referred to any body of knowledge, and the term still retains some association with Ancient Greece today. As more and more fields became mathematical and scientific in the modern era – astronomy, physics, medicine and so on – they were separated from philosophy, because they were no longer connected to ancient Greece, or to the pseudo-sciences that preceded them. 

However, fields that haven’t really changed in their basic form since the ancient era – including soft social sciences, the humanities, and psychology – remain in people’s minds as a part of “philosophy”, even though philosophy should really just be regarded as epistemology.

The general conflation of philosophical ideas with specific science and ethics is, of course, nothing new. The Ancient Greeks did it, of course, and it was also prevalent in East Asia, where Wang Yangming’s philosophical claim that “action/ethics is logically fundamental, everything else derives from it” was interpreted to mean “take a lot of action!”, particularly in Japan.

(Interestingly, this confusion notably does not appear to exist in mainline Indian philosophy. E.g. the Bhagavad Gita seemed to distinguish between philosophy and ethics pretty clearly.)