Living in an age full of ever-improving technology and scientific understanding, we may sometimes be inclined to think that observation and measurement constitute the only way to get a hold of reality, but there is a long history in philosophy of great thinkers questioning what it means exactly for something to count as evidence, and this, as you may already suspect, is a question that lies beyond the scope of science.In fact, when philosophy was just being articulated for the first time in the minds of the pre-Socratic philosophers, one of the greatest intellectual battles (and one that hasn't been fully resolved yet) was held between Heraclitus and Parmenides.
Heraclitus argued that the basic nature of the universe was change (or becoming), and that experience and observation were the methods to acquire knowledge.Parmenides, on the other hand, thought that observation, partly by virtue of its subjectivity, was not a reliable method of inquiry. Instead, he favored the cold rigor of logic and argument, and argued, consequently, that reality must be static (or being).
If you want to get an idea of some of the arguments proposed by these emblematic figures, and the radically different world-views their arguments entail, here is a three-minute tongue-in-cheek animation:
Well, wouldn't you know it, despite the many ways in which we have come to provisionally adopt a practical compromise between these two approaches to reality and knowledge, the intellectual debate rages on, as philosopher Raymond Tallis explains in this episode of Philosophy Bites:
Most problems in philosophy, I dare say, are somehow reducible to some version of the battle between Heraclitus and Parmenides. What do you think? And who do you favor?
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