This quote emphasizes the importance of diversification and adaptability, particularly in the context of oil, but it can be applied more broadly as well. The safety and certainty that Churchill refers to can be interpreted as the security and reliability that come from not being overly dependent on any one source or type of oil. By encouraging variety, he advocates for the exploration of different types of energy sources, as well as different geographical locations for oil extraction and production.

The concept of variety here can also be understood as a call for innovation and evolution, as sticking to one method or source may not be sustainable in the long run. It’s a reminder that to ensure longevity and stability in any industry, one must remain open to change and be willing to adapt.

Applying this idea to today’s world, one could consider the ongoing push towards renewable energy sources. As we become more aware of the environmental impact of traditional oil, the ‘safety and certainty’ now lies in diversifying our energy portfolio to include solar, wind, hydroelectric and other renewable sources.

In terms of personal development, this quote suggests that relying too heavily on one skill, one plan, or one way of thinking may not provide long-term security. Just like in the oil industry, safety and certainty in our personal and professional lives often come from variety – from being adaptable, from learning a range of skills, and from being open to new ideas and perspectives. This way, when circumstances change, we are better equipped to handle new challenges and opportunities.