astronomy

Hicetas

Hicetas is a astronomy topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Hicetas rather than just read about it. In short: Hicetas (Ancient Greek: Ἱκέτας or Ἱκέτης; c. 400 – c. 335 BC) was a Greek philosopher of the Pythagorean School. He was born in Syracuse, Magna Graecia.

Key takeaways

Hicetas belongs to astronomy; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Hicetas to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Hicetas from memory before moving on to harder problems.

Reference excerpt

Hicetas (Ancient Greek: Ἱκέτας or Ἱκέτης; c. 400 – c. 335 BC) was a Greek philosopher of the Pythagorean School. He was born in Syracuse, Magna Graecia. Like his fellow Pythagorean Ecphantus and the academic Heraclides Ponticus, he believed that the daily movement of permanent stars was caused by the rotation of the Earth around its axis. When Nicolaus Copernicus referred to Nicetus Syracusanus (Nicetus of Syracuse) in De revolutionibus orbium coelestium (1543) as having been cited by Cicero as an ancient who also argued that the Earth moved, it is believed that he was actually referring to Hicetas. Copernicus, searching for ancient views on earth motion, said that he "first ... found in Cicero that Hicetas supposed the earth to move." Cicero refers to Hicetas in the Academica, volume II, citing in turn Theophrastus. According to Heath:

Cicero [says] “Hicetas of Syracuse, as Theophrastus says, holds that the heaven, the sun, the moon, the stars and in fact all things in the sky remain still, and nothing else in the universe moves, except the earth; but as the earth turns and twists about its axis with extreme swiftness, all the same results follow as if the earth were still and the heaven moved". This is of course not well expressed ... but Cicero means no more than that the rotation of the earth is a complete substitute for the apparent daily rotation of the heaven as a whole.

References

Further reading Leonid Zhmud (2012). Pythagoras and the Early Pythagoreans. Translated by Kevin Windle and Rosh Ireland. Oxford University Press. pp. 20, 108, 114, 130, 325, 338, 340, 393, 405, 416, 422, 428, 432, 455. doi:10.1093/acprof:oso/9780199289318.001.0001. ISBN 978-0-19-928931-8.

Worked examples

Example 1 — a first encounter with Hicetas

Start with the simplest possible case. Write down what Hicetas claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In astronomy, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Hicetas before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Hicetas ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Hicetas

In research: Hicetas appears in astronomy research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Hicetas in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Hicetas is common in secondary-school and first-year university syllabi. It links to neighbouring topics 330s BC deaths, 400s BC births, 4th-century BC Greek philosophers, so understanding it makes those chapters shorter.
In everyday life: Look for Hicetas outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Hicetas in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Hicetas means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Hicetas out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Hicetas in simple terms?

Hicetas (Ancient Greek: Ἱκέτας or Ἱκέτης; c. 400 – c. 335 BC) was a Greek philosopher of the Pythagorean School. He was born in Syracuse, Magna Graecia.

Why does Hicetas matter?

Because it connects several astronomy ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Hicetas?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Hicetas.