In any field of endeavor, it is impossible to make a significant contribution without first being strongly influenced by past achievements within that field.
To take up any field, inspiration is must. Inspiration is the coercion required to hold on to a field and make significant contributions in it. This inspiration can be attained by knowing the basics and past achievements in that particular field. Therefore, it is true that to make a contribution in a field, some influence from past achievements is necessary. However, it is NOT impossible to make these contributions without this influence. Hence, the assertion is only partially agreeable.
When we look back in time, in most of the cases the past discoveries and inventions are the ones that had driven many people to work further and contribute more in many fields. For example, the invention of more sophisticated automobiles we have today which were developed after the invention of a wheel. The invention of computers inspired many engineers to work further. This led to the development of advanced computer we use today, from the computers in the past, which occupied almost an entire room. We can have many more examples like these.
In addition to this sometimes the discrepancies in the past achievements instill curiosity among people leading to the development of remarkable theories. As an example to this we have the most popular Einstein's theory of relativity which was formulated due to the discrepancies in the classical theory of physics. And now Einstein's theory inspired many scientists like Stephan hawking who made significant contribution in theories like the Big bang theory.
Therefore, most of the contributions that are being made now and that had been made in the past are due to the influence from preceding achievements. Being influenced by past events doesn't mean that the current achievements lack inventiveness. It is not like the past achievements are merely being replicated. They just provide us with the basic tools with which we can proceed and make more innovative contributions in a field.
However, there are a few exceptional people who have tremendous potential to make the beginning without any influence from the past. These are called "pioneers". Although, happening of such events is very rare there are people like Socrates, who was the first person to indicate that the earth is round. Then we have Sir Issac Newton who discovered gravity from the observation of an apple falling from a tree and many more. After all to have past achievements there must be a beginning somewhere.
In the light of the above discussion, to conclude, I would like to point out that even though past achievements guide us and provide the necessary inspiration for any further contributions most of the time, it is still possible to make a start without any influence from past. Therefore, I concede only to some extent with the assertion that past achievements are must to make a significant contribution in any field of endeavor.