And after looking at the evidence, it has convinced me that nuclear power is indeed essential if we want to address climate change seriously.
Of course, the posthumous polemics about the Spanish war are legitimate, and indeed essential - but only if we separate out debate on real issues from the parti pris of political sectarianism, cold-war propaganda and pure ignorance of a forgotten past.
The question Martin Amis asked was legitimate, indeed essential.
This is a fair, indeed essential, requirement of any ceasefire.
But to talk of German responsibility for the crimes was legitimate and, indeed, essential.
Sleep is a normal, indeed essential part of our lives.
However, whether a strong signal is indeed essential for efficient entry into and completion of a developmental pathway and, if not, how cells cope with premature, delayed, reduced, or increased signals, remains a fundamental, unsolved question.
Since the first quarter of the 20th century many historians of religions have accepted the notion of the sacred and of sacred events, places, people, and acts as being central in religious life if not indeed the essential reality in religious life.
If indeed MMP-2 activity is essential to hepatocyte migration, then its low expression within nodular hepatocytes might help in explaining their inability to crawl in between surrounding hepatocytes and their lack of integration into the host liver, thereby giving rise to proliferative focal lesions.
A line of argument that could be developed on this basis suggests that if indeed there are such things as essential particularized properties that are "possessed" by composite objects, then they are in fact to be identified with those objects.
