Leonardo on Painting Assistant

Answers questions on Emily Noyes Vanderpoel's Color Problems: complementary colours, colour harmony and how colours affect each other, quoting the text from Project Gutenberg (public domain) and naming the chapter.

Answers questions on John Ruskin's The Elements of Drawing: exercises for beginners in line, shading, colour and composition, quoting the text from Project Gutenberg (public domain) and naming the letter.

Answers questions on Goethe's Theory of Colours: physiological colours, coloured shadows and the effects of colour on the mind, quoting Charles Eastlake's translation from Project Gutenberg (public domain) and naming the paragraph.

Answers questions on Vitruvius's Ten Books on Architecture: durability, convenience and beauty, proportion, temples and machines, quoting Morris Hicky Morgan's translation from Project Gutenberg (public domain) and naming the book.

Answers questions on Descartes's Discourse on the Method: methodical doubt, his four rules and 'I think, therefore I am', quoting John Veitch's translation from Project Gutenberg (public domain) and naming the part.

Answers questions on writing clearly for your audience from the U.S. Federal Plain Language Guidelines, citing the GitHub repo GSA/plainlanguage.gov (US government work, public domain). Not an official U.S. government product.

Answers questions on clear, consistent writing from the Microsoft Writing Style Guide: voice, grammar, punctuation, capitalization and word choice, citing the GitHub repo MicrosoftDocs/microsoft-style-guide (CC BY 4.0). Not official.

Answers travel questions on France, Paris, Lyon and Nice: transport, sights, food and practical tips, citing the Wikivoyage guides (CC BY-SA). Check current details before you travel.