"In reply, I can only plead that a discovery which seems to contradict the general tenor of previous investigations is naturally received with much hesitation"

Charles Lyell's quote speaks with the problem of accepting brand-new discoveries that contradict the accepted knowledge of the time. He acknowledges that it is natural to be reluctant when presented with something that goes versus the grain of what is currently understood. This is due to the fact that it is human nature to be resistant to alter and to be skeptical of originalities. It is also tough to accept something that goes against the accepted knowledge of the time, as it can be viewed as a challenge to the status quo. Lyell's quote is a suggestion that it is necessary to remain unbiased and to be ready to think about new ideas, even if they appear to oppose what is currently known. It is just through this openness that progress can be made and new discoveries can be made.