How does the "old art" view of cryptography compare to the "new science" view?

Old cryptography was about secrecy with heuristic security; modern cryptography is a broad science with formal proofs and public-key systems.

Prof. U. Maurer (ETH Zurich) contrasts these two paradigms:

Additional modern concerns beyond this comparison:

• Key size → Secure implementation
• Brute force attacks → Time-memory attacks / side channel attacks
• Moore's Law → Quantum computing threat

Tip: This shift happened roughly in the 1970s — the transition from "secret military art" to "open academic science" is what made modern digital security possible.