OE1-2.5 Science and Logic

What this is and why it exists

The most transferable material in this whole course is in this topic, and it is the logic rather than the astronomy.

A formal account of what counts as a valid source of knowledge is epistemology by any name. Set beside a modern account of scientific method, it makes both easier to see.

The vocabulary

• Pramana — a recognised means by which valid knowledge is obtained.
• Perception — knowledge from direct sensory contact.
• Inference — knowledge from reasoning, given something already known.
• Comparison — knowledge from likeness to something already familiar.
• Testimony — knowledge from a reliable source's word.
• Postulation — assuming what must be true to make an observed fact intelligible.
• Non-apprehension — knowing something is absent because it is not perceived.
• Tarka — reasoning, including the analysis of inference.
• Fallacy — a form of reasoning that appears valid and is not.
• Luni-solar calendar — one reconciling the cycles of the moon with the year of the sun.

The mental model

Take the logic first, because it is what you will use.

The question is simple and deep: how does anyone come to know something? The tradition answers by listing means and examining each. Perception, where the senses make contact. Inference, where something known leads to something not observed, as smoke leads to fire. Comparison, where a new thing is known through its likeness to a familiar one. Testimony, where a reliable source is the ground. Postulation, where something must be assumed to make an observed fact intelligible. And non-apprehension, where the absence of something is known by its not being perceived.

Different schools accept different numbers of these. Some accept all six, some fewer, and the arguments about which belong are part of the material rather than a distraction from it. A school that reduces comparison to a form of inference is making a case, and the case is worth following.

Now set that beside a modern account of scientific method, and the comparison teaches more than either alone.

Both take perception as basic and both treat inference as the main engine. Both are wary of testimony while depending on it constantly, because no individual verifies everything they know. The modern account puts far more weight on deliberate experiment, on measurement, and on prediction that could fail. The older account gives a more careful analysis of inference itself, of what makes an inference valid, and of the ways it goes wrong.

That last part is the most directly useful. The catalogue of fallacies lists reasoning errors that look like reasoning. An argument that assumes what it sets out to establish. One where the connection between two things is not universal. One where the counter-case was overlooked. Those are the same errors a modern logic course teaches, arrived at independently. Two traditions converging on them is itself evidence that they are real.

The astronomy is where care is most needed. Attend to the evidence and the reasoning rather than to the question of who was first. Priority arguments are usually unproductive and often unanswerable. What can be examined is what a text states, what a model would predict, and whether observations were recorded that the model accounts for.

The geometric constructions for altar building are worth doing rather than reading. They give methods for constructing shapes of a specified area, and for converting one shape into another of equal area. They also contain the relationship between the sides of a right-angled triangle. Working one construction with a ruler and a cord teaches more than several paragraphs about them.

The letter-to-number encoding is an elegant solution to a real problem. Numerical values were assigned to consonants, so a number could be written as a word or a phrase. A table of astronomical constants could then be carried inside verse. Verse survives oral transmission far better than digit strings do, because metre and meaning both resist corruption where a mistyped digit leaves no trace. It is a checksum made of poetry.

The calendar is a good demonstration of applied computation. Lunar months and the solar year do not divide evenly. Reconciling them needs a rule for inserting extra months, and that rule needs real astronomy to keep the seasons in place. Every luni-solar calendar faces this and solves it somehow.

The proposal about Sanskrit and computer languages appears again here and should be treated exactly as in the earlier topic. Separate the structural observation, which is well founded, from the practical conclusion, which is contested. Repeating a contested statement as settled is the failure this course is most exposed to. Noticing that is part of what the logic in this topic is for.

The definition of health as something more than the absence of disease closes the course, and it is worth thinking about on its own terms. It is a definitional position rather than an empirical statement, and it has consequences for what a system of medicine sets out to do.

What you should now be able to explain or do

Name the recognised means of valid knowledge and give an example of each. Say why schools disagree about how many there are, and what such a disagreement argues. Compare the tradition with a modern account of scientific method on inference, experiment and testimony. Identify the fallacies and say why two traditions converging on them is evidence. Explain the letter-to-number encoding as a solution to a transmission problem.

Check yourself