Crossword

1. persistence in doing something
4. based on, concerned with, or verifiable by observation or experience rather than theory or pure logic
6. process by which electricity or magnetism is passed between two objects or circuits without them touching each other
9. according to the rules of logic or formal argument
10. use of the imagination or original ideas
13. facts and statistics collected together for reference or analysis
15. fundamental units of the brain and nervous system
16. skills, methods, and processes used to achieve goals
17. derived from an Irish surname that originated in County Cork, meaning saffron-colored.
19. capable of making mistakes
20. one of the greatest philosophers of science of the 20th century. He was a social and political philosopher of considerable stature, a self-professed critical-rationalist, a dedicated opponent of all forms of scepticism, conventionalism, and relativism in science and in human affairs generally and a committed advocate and staunch defender of the ‘Open Society’.

2. a virtual assistant that is part of Apple Inc.'s operating system
3. lacking a moral sense
5. standard, perspective, or set of ideas
7. the star of the north
8. comprehension of the parts of something as intimately interconnected and explicable only by reference to the whole
11. not certain or fixed
12. hard-wearing
14. a Russian chess grandmaster, former World Chess Champion, writer, and political activist and commentator.
18. relating to or involving iteration