Weeks later, on 10 April, Franklin wrote to Crick for permission to see their model. Franklin retained her scepticism for premature model building even after seeing the Watson–Crick model, and remained unimpressed. She is reported to have commented, "It's very pretty, but how are they going to prove it?" As an experimental scientist, Franklin seems to have been interested in producing far greater evidence before publishing-as-proven a proposed model. Accordingly, her response to the Watson–Crick model was in keeping with her cautious approach to science.